Doppler frequency shift detection method and device based on photonic technology

Abstract

The invention discloses a Doppler frequency shift detection method and device based on the photonic technology. A continuous laser light source is divided into two branches through a coupler, wherein one branch enters a carrier inhibition type single side band modulation module and is modulated by emitted microwave / millimeter wave signals, and a generated single optical side band enters an electro-optical modulator and is modulated by the microwave / millimeter wave signals which are reflected and contain Doppler frequency shift information; the second branch enters an acoustic optical modulator to conduct certain optical frequency shift; the two branches enter a low-speed photoelectric detector after outputs of the two branches are merged, and the two branches generate low-frequency radio frequency signals at beat frequency; the generated radio frequency signals are subjected to spectral analysis, and then the Doppler frequency shift amount and direction can be obtained. The Doppler frequency shift detection method and device are based on the photonic technology, the structure is simple, the whole detection process has nothing to do with the carrier frequency of the microwave / millimeter wave signals to be detected, and Doppler frequency shift detection can be carried out within a wide frequency band range.

Description

technical field [0001] The invention relates to the fields of microwave detection, microwave photonics and radar, especially the photonic Doppler frequency shift detection technology. Background technique [0002] The Doppler frequency shift is generated by the relative motion between the wave source and the observer, and has important applications in the fields of wireless communication, astronomical measurement, medical imaging, electronic warfare, and radar. In these applications, the key is to be able to obtain the Doppler frequency shift quantitatively and accurately. However, the current estimation and analysis of Doppler shift is facing a series of challenges. On the one hand, in order to accurately detect low-speed moving objects, Doppler frequency shift schemes and devices with good resolution are urgently needed; Almost spanning the range of 0-300GHz, this requires that the Doppler frequency shift detection process has nothing to do with the signal frequency band...

AI Technical Summary

Problems solved by technology

[0004] It should be pointed out that the above-mentioned photonics detection scheme is mainly aimed at measuring the frequency and angle of arrival parameters of microwave signals, and there are few reports on photonic Doppler frequency shift measurement methods and technologies.

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